Machine suspension system

ABSTRACT

A machine includes a prime mover having a power take-off, a chassis configured to support at least an operator and the prime mover, a subframe pivotally coupled to the chassis about a pivot axis at a first location, at least one drive device configured to drive wheels of the machine, a drive belt and pulley arrangement. The subframe is further coupled to the chassis via at least one suspension device at a second location. The at least one drive device is driven by the prime mover and is coupled to the subframe. The pulley arrangement is configured to direct the drive belt from the power take-off of the prime mover to at least one drive pulley on the at least one drive device. The pulley arrangement comprises an idler pulley having a diameter and a rotational axis. The idler pulley is coupled to the chassis such that the rotational axis is spaced from the pivot axis by no greater than 1.5 times the diameter.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/018,020, filed Jun. 15, 2018, which is a continuation of U.S. patentapplication Ser. No. 15/150,485, filed May 10, 2016, now U.S. Pat. No.10,005,437, which claims the benefit of and priority to U.S. ProvisionalPatent Application No. 62/131,738, filed Mar. 11, 2015, the entirecontents of each of which are incorporated herein by reference.

BACKGROUND

The present invention relates to a suspension system used on machinessuch as lawn and garden equipment, such as zero-turn radius (ZTR)mowers. Typically, ZTR mowers comprise unsuspended right and left drivewheels operably coupled to a mower frame, with at least one front casterwheel also coupled to the mower frame. However, independently-suspendedright and left drive wheels for ZTR mowers have been shown in U.S. Pat.Nos. 5,946,893, 6,062,333, 6,170,242, 6,244,025, 6,460,318, 6,510,678,6,857,254, and 7,107,746, each of which is incorporated herein byreference. These patents show several variations ofindependently-suspended right and left drive wheels for ZTR mowers, eachembodiment including a prime mover such as an internal combustionengine, a hydraulic pump for each respective drive wheel being operablycoupled to the internal combustion engine, and a hydraulic motor foreach respective drive wheel being operably coupled to the respectivehydraulic pumps. Both the internal combustion engine and the respectivehydraulic pumps are connected to the frame of the ZTR mower in anunsuspended manner, wherein the hydraulic pumps are mechanically coupledand driven by the internal combustion engine via, for example, abelt-and-pulley system. The hydraulic pumps are then coupled to therespective hydraulic wheel motors via a series of hoses, wherein thehydraulic wheel motors are mounted on a suspension platform to allow forindependent suspension of each of the drive wheels. The delivery ofhydraulic fluid from the hydraulic pumps to the hydraulic wheel motorsenables zero-turn radius drive capabilities, as is known in the art.

Recently, the use of hydrostatic transmissions known as hydrostatictransaxles has become prevalent in the ZTR mower industry. Hydrostatictransaxles combine the hydraulic pump and hydraulic wheel motor into asingle unit, thereby simplifying and reducing the overall cost of thedrive system of ZTR mowers and other hydraulically-driven devices.Typically, two hydrostatic transaxles are used, one for each drive wheelof the ZTR mower. Similar to the system described above, the hydraulicpump of the hydraulic transaxle is mechanically driven by an internalcombustion engine (or similar drive unit) via a belt-and-pulley system,and the hydraulic pump in turn drives the hydraulic motor for each drivewheel. However, due to the integration of the hydraulic pump andhydraulic wheel motor into a single unit, suspension of the drive wheelson a ZTR mower utilizing hydrostatic transaxles presents severalchallenges. Foremost of those challenges is the variation in belt anglebetween the drive pulley coupled to the output shaft of the internalcombustion engine and the driven pulley(s) of the hydraulic pump on thehydrostatic transaxle. If the belt angle between the drive and drivenpulley(s) is too great, the belt may run off of one or more the pulleysand render the drive system inoperable. These challenges were addressedin the ZTR mower suspension system shown in commonly-owned U.S. Pub.2013/0291508, incorporated herein by reference. However, the systemshown in that publication was directed to a larger, commercial-style ZTRmower, wherein the engine (and thus power take-off) positioning wassignificantly behind the hydrostatic transaxles, thereby enabling thesystem's pulleys to be located on a suspended subframe withoutsignificant variations in belt angle that would potentially cause thebelt to “jump” or run off of one or more pulleys. Thecomponent-placement advantages of this larger machine would notnecessarily be present in a smaller ZTR mower.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of an example machine having an examplesuspension system.

FIG. 2 is a perspective view of select machine and suspensioncomponents.

FIG. 3 is a top view of select machine and suspension components.

FIG. 4 is a top perspective view of a portion of the example machine andsuspension of FIG. 1.

FIG. 5 is a rear perspective view of a portion of the example machineand suspension of FIG. 1

FIG. 6 is a sectional view of a portion of an example machine andsuspension of FIG. 1.

FIG. 7 is a bottom view of a portion of the example machine andsuspension of FIG. 1 illustrating various alternative idler pulleypositions.

FIG. 8 is a top front perspective view illustrating an example parkingbrake system of the example machine of 1.

FIG. 9 is a top rear perspective view illustrating the example parkingbrake system.

FIG. 10 is a bottom perspective view illustrating the example parkingbrake system.

FIG. 11 is a fragmentary perspective view of a portion of the parkingbrake system in a brake disengaged position.

FIG. 12 is a fragmentary perspective view of the portion of the parkingbrake system in a brake engaged position.

FIG. 13 is a sectional view of the example machine illustrating parkingbrake system components.

FIG. 14 is a perspective view of another example hydrostatic transaxleand associated portions of another example parking brake system.

DETAILED DESCRIPTION OF EXAMPLES

FIG. 1 illustrates of an example machine, an example piece of lawn andgarden equipment, shown as a zero turn radius (ZTR) lawnmower 100. ZTRmower 100 of FIG. 1 comprises a prime mover 102, such as an air-cooledinternal combustion engine, electric motor, etc., wherein prime mover102 is supported on a chassis 104. An operator seat 106 is coupled tochassis 104 forward of prime mover 102, enabling an operator to controlZTR lawnmower 100 while seated in seat 106 and having their feet placedon footplate 108. Two control levers 110 a, 110 b are configured to bepivotally actuated by the operator to enable forward movement, reversemovement, and turning of ZTR lawnmower 100, as is well known in the art.

Control levers 110 a, 110 b are coupled to respective hydrostatictransaxles (not shown) to power respective right and left drive wheels112. In lieu of hydrostatic transaxles, drive via independent pump andwheel motors or independent electric drive motors is also possible.Additionally, it is possible for a single transmission (hydraulic orotherwise) to drive both right and left drive wheels 112. Two frontcaster wheels 114 a, 114 b allow the mower to be easily maneuvered in azero turn radius fashion. In the example illustrated in which theillustrated machine comprises a lawnmower, a mower deck 113 is hung fromchassis 104, wherein the mower deck supports one or more mowing blades115 powered by prime mover 102.

FIGS. 2-3 are partial views of various components of ZTR mower 100. Asshown by FIGS. 2 and 3, chassis 104 comprises two longitudinal supportbeams 116 a, 116 b, a front cross beam 118 a, and a central plate 121coupled to respective longitudinal support beams 116 a, 116 b. Chassis104 also comprises a prime mover mounting plate 120 upon which primemover 102 is coupled. Additionally, a suspended subframe 105 ispivotally mounted to chassis 104 about a pivot axis A at respectivepivot points 124 a, 124 b. Suspended platform 105 supports thereonintegrated hydrostatic transaxles 130 a, 130 b, which integrally containboth a hydraulic pump and a hydraulic motor therein for driving drivewheels 112. Control cables 132 a, 132 b for each control lever 110 a,110 b are coupled to bell cranks 134 a, 134 b on respective hydrostatictransaxles 130 a, 130 b, which enables forward and reverse control oftransaxles 130 a, 130 b in a manner known in the art. While cables 132a, 132 b are shown, it is also possible for the connection betweencontrol levers 110 a, 110 b and hydrostatic transaxles 130 a, 130 b tobe via other types of suitable linkages.

Suspended subframe 105 comprises longitudinal support beams 122 a, 122b, wherein the distal ends of longitudinal support beams 122 a, 122 bare coupled to respective suspension devices 126 a, 126 b. Suspensiondevices 126 a, 126 b could be any suitable suspension mechanism such asa coil-over-shock device, a dampener, etc. Suspension devices 126 a, 126b are also coupled to respective supports 128 a, 128 b mounted onlongitudinal support beams 116 a, 116 b of chassis 104. With thisconfiguration, subframe 105 is pivotally suspended from chassis 104about pivot axis A such that drive wheels 112 are capable ofsubstantially vertical translation as ZTR mower 100 moves over roughterrain, etc. FIG. 2 shows subframe 105 in a substantially compressedposition, but it is to be understood that subframe 105 may typically beat angled at various positions with respect chassis 104 originating atpivot points 124 a, 124 b, generally dependent upon the presence of anoperator, condition of the terrain, etc. As hydrostatic transaxles 130a, 130 b are coupled to subframe 105, they too are capable of verticaltranslation about pivot axis A. Conversely, because prime mover 102 isaffixed to mounting plate 120 on chassis 104, prime mover 102 does notmove in concert with suspended subframe 105.

FIG. 3 is a top view of various example ZTR mower components. Asdiscussed above with respect to FIG. 2, suspended subframe 105 pivotsabout a pivot axis A from chassis 104. Respective longitudinal supportbeams 122 a, 122 b of subframe 105 act to at least partially supporthydrostatic transaxles 130 a, 130 b (collectively referred to astransaxles 130), which are coupled to drive wheels through respectivewheel hubs 131 a, 131 b. In order to transfer power from a prime mover(not shown) to the respective hydrostatic transaxles 130 a, 130 b, anengine drive pulley 135 is coupled to a power take-off (PTO) shaft ofthe prime mover and connected via a belt 137 using a pulley arrangementto be discussed in further detail below. A PTO clutch 136 is alsocoupled to the PTO shaft of the prime mover to drive the blades 108 of amower deck 104 coupled to chassis 104 via a separate belt (also notshown). Belt 137 could be any suitable drive belt, but is preferably adouble-A or double-V-type belt to allow the belt to drive pulleys onboth its inside and outside surfaces.

FIGS. 4 and 5 illustrate an example pulley arrangement 141 that guidesand directs belt 137 so as to drive each of hydrostatic transaxles 130.Pulley arrangement comprises idler pulleys 138, 140, 142 and drivepulleys 144 a, 144 b. Belt 137 runs from PTO clutch 136 to idler pulleys138, 140, wherein idler pulleys 138, 140 are mounted on central plate121 of chassis 104. Accordingly, idler pulleys 138, 140 do not pivotabout pivot axis A or otherwise move with vertical translation ofsuspended subframe 105. From idler pulleys 138, 140, belt 137 runs todrive pulleys 144 a, 144 b on respective hydrostatic transaxles 130 a,130 b in order to enable hydraulic drive of the transaxles 130 a, 130 b.Idler pulley 142 is coupled to a rear cross beam 118 b of subframe 105to maintain tension and provide sufficient belt-wrap of belt 137 arounddrive pulleys 144 a, 144 b.

As mentioned above, idler pulleys 138, 140 are mounted on central plate121 of chassis 104, while drive pulleys 144 a, 144 b are coupled tohydrostatic transaxles 130 a, 130 b, meaning drive pulleys 144 a, 144 balso move in concert with any translation of suspended subframe 105. Asidler pulleys 138, 140 are stationary (i.e., do not pivot with respectto pivot axis A) and drive pulleys 144 a, 144 b move with suspendedsubframe 105, the angle of belt 137 between these sets of pulleyschanges with the various the suspension conditions of subframe 105.Accordingly, proper placement of idler pulleys 138, 140 is important toavoid significant changes in belt angle during operation of the mower,as such significant changes may cause belt 137 to “jump” duringoperation and disengage belt 137 from the drive system.

FIGS. 6 and 7 illustrate examples for the placement of idler pulleys130, 140. As shown by FIG. 6, in one implementation, the rotational axes150 of idler pulleys 138, 140 are perpendicular to and substantially inline with pivot axis A of suspended subframe 105. For the purposes ofthis embodiment, idler pulleys 138, 140 being “substantially” in linewith the pivot axis A may mean that the pulleys are directly in linewith pivot axis A (with no perceivable offset, intersecting pivot axisA), within one pulley diameter forward of pivot axis A, or a greaterdistance forward of pivot axis A within the confines of chassis 104.

In the example illustrated in FIG. 6, axes 150 of idler pulleys 138, 140are directly in line with pivot axis A, intersecting pivot axis A. As aresult, as indicated by radius lines 152, the belt angle between idlerpulleys 138, 140 and drive pulleys 144 a, 144 b is as small as possible,regardless of the suspension condition of subframe 105. In other words,the length of belt 137 insubstantially changes or does not change inresponse to the pivoting of subframe 105. Because the length of belt 137does not change despite the pivoting of subframe 105, the risk of belt105 jumping and becoming disengaged from any of the pulleys of thepulley arrangement 141 is reduced.

FIG. 7 is a top view of portions of mower 100 illustrating alternativepositions for idler pulleys 138, 140. In other implementations, therotational axes 150 of idler pulleys 138, 140 may be spaced, forwardlyor rearwardly, from pivot axis A by a distance D of up to 1.5 times thediameter of at least one of idler pulleys 138, 140. In suchimplementations, the length of belt may more substantially change assubframe 105 pivots, possibly requiring more robust and complex belttake up assemblies.

In some implementations, idler pulleys 138, 140 may alternatively be setslightly closer to the front of the mower (i.e., in the direction ofcontrol levers 110 a, 110 b. For example, in one implementation, idlerpulleys 138, 140 may have rotational axes 150′ which are located lessthan or equal to 1 inch of pivot axis A as shown in FIG. 6. In otherimplementations, idler pulleys 138, 140 may be positioned a distance ofone pulley diameter forward of pivot axis A without substantial changingthe complexity of the system. As illustrating FIG. 7, in someimplementations, idler pulleys 138, 140 may be positioned even furtherforward of pivot axis A (by greater than one pulley diameter) dependingon the overall layout of the mower and intervening components, but thisagain may add to the complexity of the belt take-up assembly.

FIGS. 4 and 5 illustrate one example belt take-up assembly 190 fortaking up slack in belt 187 that may result from the pivoting ofsubframe 105 about pivot axis A. Belt take-up assembly 190 helpsmaintains belt tension on the system (i.e., “take-up”). In the exampleillustrated, belt take up assembly 190 comprises a movable support thatmovably supports the rotational axis of at least one of idler pulleys138, 140 for movement between different positions to relocate therotational axis and a bias mechanism resiliently biasing the idlerpulley towards a predefined position for the rotational axis. In theexample illustrated, the movable support comprises an idler arm 194having a first end portion pivotally coupled to chassis 104 for pivotalmovement about axis 195, a central portion rotatably supporting theidler pulley, idler pulley 140 for rotation about axis 150 and a secondend portion resiliently biased towards a preset a predefined position.In the example illustrated, the bias mechanism comprises a tensionspring 196 interconnecting the second end portion of arm 194 and chassis104. During pivoting of subframe 105, spring 196 stretches or constrictsas the rotational axis pulley 140 changes to accommodate the change inthe length of segments or strands 197 of belt 187, extending between theidler pulleys 138, 140 and the drive pulleys 144 a and 144 b. In otherimplementations, belt take up assembly 190 may have otherconfigurations.

FIGS. 8-13 illustrate an example parking brake system 200 for mower 100.Parking brake system 200 is configured to brake wheels 112 when themower 100 is in a parked or stopped position. Parking brake system 200comprises flexible cable 202, control arm interface 204, cable mount 206and brake interface 208. Flexible cable 202 extends between control arm110 a (shown in FIGS. 1-3) and each of hydrostatic transaxles 130 so asto transmit motion of control arm 110 a to an internally located brakingmechanism within each of hydrostatic transaxles 130. In the exampleillustrated, flexible cable 202 comprises a Bowden cable, a cablecomprising an inner flexible cable 210 and an outer guiding sheath 212(shown in FIG. 12). The inner flexible cable 210 is connected to thecontrol arm interface 204 and the brake interface 208 at opposite ends,wherein the inner flexible cable is pushed and pulled through, along andrelative to the outer flexible sheath 212. The outer flexible sheath 212has a first end 214 (as shown in FIG. 11) fixedly coupled to chassis 104proximate to control arm interface 204 and a second end 216 fixedlycoupled to cable mount 206 supported by subframe 105. The outer flexiblesheath 212 has sufficient slack between its ends such that the outerflexible sheath may accommodate movement of cable mount 206 resultingfrom pivotal movement of suspension 105

FIG. 11 illustrates control arm interface 204 in more detail. Controlarm interface 204 comprises rod 220 and bell crank bracket 222. Rod 220is coupled between control arm 110 a and bell crank bracket 222. In oneimplementation, rod 220 is affixed at one end to control arm 110 a and asecond end to bell crank bracket 222.

Bell crank bracket 222 comprises a bracket pivotably coupled to chassis104 for rotation about axis 226. Bracket 222 is connected to rod 220 ona first side of axis 226 and is connected to flexible cable 210 on asecond side of axis 226. As shown by FIG. 12, pivoting of control arm110 a outwards, about axis 230 drives rod 220 in the direction indicatedby arrow 232 which results in bell crank bracket 222 being rotated inthe direction indicated by arrow 234. Rotation of bell crank bracket 222and the direction indicated by arrow 232 results in table 210 beingpulled through and relative to sheath 212 in the direction indicated byarrow 236. Such motion is transmitted through an along sheath 212 tobrake interface 208.

Cable mount 206 comprises a structure affixed to and carried by subframe105 so as to pivot with subframe 105. Cable mount 206 secures end 216 ofsheath 212 to subframe 105. Cable mount 206 ensures that the sheathabout flexible cable 210 also moves with the pivoting of subframe 105,wherein the actual length of the flexible cable 210 within sheath 212does not change.

Brake interface 208 comprises one or more structures interconnectingflexible cable 216. Brake interface 208 comprises spring 250, bracket252, lever 254 and bias 256. Spring 250 comprises a tension springconnected between cable 210 and bracket 252. Spring 250 exerts a biasthrough flexible cable 210 to bell crank bracket 222, opposing outwardpivoting of control arm 110 a. Spring 250 further transmits motion ofcable 210 to bracket 252.Bracket 252 comprises a non-flexible frame or member that interconnectsspring 250 and lever 254. Bracket 252 further interconnects spring 250to a second lever 254 associated with the other hydrostatic transaxle131 b. In the example illustrated, bracket 252 comprises an inflexibleor rigid U-shaped frame having opposing spaced legs extending onopposite sides of PTO clutch 136 and connected to each of the levers 254of the two hydrostatic transaxles 131. In other implementations, bracket252 may have other configurations.Lever 254 comprises a rigid brake engaging member pivotally connected tobracket 252 at one end and connected to a shaft or rod that rotatesabout axis 260 and that extends into the respective transaxle 130 a, 130b to an internal cog or other component (not shown) within transaxles130 a, 130 b when in the “park” position to prevent rotation of thedrive wheels. Spring 256 comprise a tension spring having one endconnected to or affixed relative to an outer housing of the respectivetransaxle 130 and having another end connected to lever 254 to biaslever 254 to a predefined position, such as a position in which theinternal brake of the transaxle 130 is disengaged. In otherimplementations, other mechanisms may be utilized to bias lever 254 to apredefined position.

Due to the suspended nature of subframe 105, it is important thatU-shaped frame 150 remain stationary relative to transaxles 130 a, 130 bunless actuated by the user to apply the parking brake. Accordingly,while flexible cable 210 may move with corresponding pivotal movement ofsubframe 105, spring 152 and U-shaped frame 150 are mounted only tocomponents of subframe 105 such that translation of the suspensionsystem alone does not move levers 254 and inadvertently actuate the cogsor other components within transaxles 130 a, 130 b to actuate the brakewhile the mower is moving.

FIG. 14 illustrates hydrostatic transaxle 330, an alternativeimplementation of hydrostatic transaxle 130 a or 130 b. Transaxle 330 issimilar to transaxle 130 except that transaxle 330 has an externalbraking mechanism comprising gear 370 and brake 372. Gear 370 is affixedto a shaft and operably coupled to the output shaft of transaxle 330 andwheel 112. Brake 372 comprises a curved toothed brake engagement memberpivotable about axis 378 between a gear engaging, braking position and awithdrawn, brake disengaged position. In such an implementation, bracket252 (shown in FIG. 13) is pivotally connected to brake 372 at connection380. In one of limitation, bracket 252 is pivotally connected to brake372 at connection 380 for each of the two transaxles 330. Similar tolever 254, brake 372 is resiliently biased towards a withdrawn positionby spring 256.

In operation, in response to lever arm 110 a being pivoted outward aboutaxis 230 as shown in FIG. 12, flexible cable 210 is pulled to pull up onspring 250. Spring 250 pulls upon bracket 250 which pivots brake 372,against the bias of spring 256, into braking engagement with gear 370.Pivoting of control arm 110 a to the inner position shown in FIG. 11results in bracket 252 pivoting brake 372 about axis 378 away from andout of engagement with brake 370. Such withdrawal to the brakedisengaged position is further assisted by the bias of spring 256.

Although the present disclosure has been described with reference toexample implementations, workers skilled in the art will recognize thatchanges may be made in form and detail without departing from the spiritand scope of the claimed subject matter. For example, although thepulley arrangement and the parking brake system are illustrated as beingutilized as part of a riding lawnmower such as a zero turn radius mower,in other implementations, we discussed pulley arrangement and parkingbrake system may be employed and other machines or other pieces of lawnand garden equipment which employ a suspension that carries drivedevices that are driven by a prime mover. Although different exampleimplementations may have been described as including one or morefeatures providing one or more benefits, it is contemplated that thedescribed features may be interchanged with one another or alternativelybe combined with one another in the described example implementations orin other alternative implementations. Because the technology of thepresent disclosure is relatively complex, not all changes in thetechnology are foreseeable. The present disclosure described withreference to the example implementations and set forth in the followingclaims is manifestly intended to be as broad as possible. For example,unless specifically otherwise noted, the claims reciting a singleparticular element also encompass a plurality of such particularelements.

What is claimed is:
 1. A machine comprising: a prime mover an enginedrive pulley coupled to the prime mover; a chassis, wherein the chassisis configured to support at least an operator and the prime mover; asubframe pivotally coupled to the chassis about a pivot axis, whereinthe subframe is further coupled to the chassis via at least onesuspension device; at least one drive device configured to drive wheelsof the machine, the at least one drive device driven by the prime mover;a drive belt; and a pulley arrangement configured to direct the drivebelt from the engine drive pulley of the prime mover to at least onedrive pulley on the at least one drive device, wherein the pulleyarrangement comprises at least one idler pulley having a diameter and arotational axis.
 2. The machine of claim 1, wherein the machinecomprises a lawn mower.
 3. The machine of claim 1, wherein the at leastone idler pulley comprises a first idler pulley having a first diameterand a first rotational axis and a second idler pulley having a seconddiameter and a second rotational axis.
 4. The machine of claim 1,wherein the at least one drive device comprises at least one hydrostatictransaxle having at least one output shaft located along a transaxleaxis and coupled to a drive wheel of the machine and wherein the atleast one drive pulley is located rearward of the transaxle axis and theat least one idler pulley is positioned forward of the transaxle axis.5. The machine of claim 4, wherein the engine drive pulley is locatedrearward of the transaxle axis.
 6. The machine of claim 1, wherein thesubframe comprises a first longitudinal support beam, a secondlongitudinal support beam, and a cross beam.
 7. The machine of claim 1,wherein the prime mover is at least one of an internal combustion engineand an electric motor.
 8. The machine of claim 1, wherein the primemover is coupled to a plate on the chassis.
 9. The machine of claim 1,wherein the idler pulley is movable to reposition the rotational axisand wherein the machine further comprises a bias mechanism resilientlybiasing the idler pulley towards a predefined position for therotational axis.
 10. The machine of claim 9, wherein the bias mechanismcomprises an idler arm rotationally supporting the idler pulley andtensioning spring coupling the idler arm to the chassis.
 11. The machineof claim 1, wherein the rotational axis of the idler pulley is offsetfrom the pivot axis.
 12. A machine comprising: a prime mover, the primemover having a power takeoff; a chassis, wherein the chassis isconfigured to support at least an operator and the prime mover; asubframe pivotally coupled to the chassis about a pivot axis, whereinthe subframe is further coupled to the chassis via at least onesuspension device; at least hydrostatic transaxle having at least oneoutput shaft having a transaxle axis, the output shaft coupled to adrive wheel of the machine, the at least one hydrostatic transaxledriven by the prime mover and coupled to the subframe; a drive belt; anda pulley arrangement configured to direct the drive belt from the powertake-off of the prime mover to at least one drive pulley on the at leastone hydrostatic transaxle, wherein the pulley arrangement comprises atleast one idler pulley having a diameter and a rotational axis, andwherein the at least one drive pulley is located rearward of thetransaxle axis.
 13. The machine of claim 12 further comprising a mowerdeck coupled to the chassis and rotationally supporting a mower blade.14. The machine of claim 12, wherein the rotational axis of the idlerpulley is spaced near the pivot axis.
 15. The machine of claim 12,further including an engine drive pulley coupled to the power takeoffand wherein the engine drive pulley is located rearward of the transaxleaxis.
 16. The machine of claim 15, wherein pulley arrangement isconfigured to direct the drive belt from the engine drive pulley to theat least one drive pulley on the at least one hydrostatic transaxle. 17.The machine of claim 12 further comprising: a parking brake systemcomprising: at least one brake engagement member actuatable to engage aparking brake on the at least one drive device; a cable mount carried bythe subframe; a flexible cable having a sheath, wherein the sheath iscoupled to the cable mount and the flexible cable is further coupled tothe brake engagement member to actuate the brake engagement member toengage the parking brake on the at least one drive device, wherein thecable mount is carried on the subframe so as to not enable the flexiblecable to actuate the brake engagement member through pivotal movement ofthe subframe alone.
 18. The machine of claim 17 further comprising acontrol member operably coupled to the flexible cable to move theflexible cable relative to the sheath to actuate the brake engagementmember to engage the parking brake on the at least one drive.
 19. Themachine of claim 18 further comprising a spring operably coupled betweenthe flexible cable and the brake engagement member.